In the era of rapid technological development nowadays, sensor technology has been constantly achieving new breakthroughs and progress. Among them, position-sensitive thin-film pressure sensors, with their unique performance and advantages, play an important role in many fields. And do they also have broad application prospects in non-industrial fields?
I. Principles of Position-Sensitive Thin-Film Pressure Sensors
Position-sensitive thin-film pressure sensors mainly achieve the precise sensing of pressure and its position based on the piezoresistive effect or capacitive effect and other principles.
From the perspective of the piezoresistive effect, when the thin film is subjected to pressure, will the resistance of the semiconductor material inside it change? And does this change in resistance have a certain functional relationship with the magnitude of the applied pressure? Moreover, by arranging multiple sensing units on the thin film, can the specific position where the pressure is applied be further determined according to the situation of resistance changes in different units?
If it is based on the capacitive effect, the thin-film pressure sensor is composed of two electrodes and an intermediate dielectric layer (the thin film). When pressure is applied to the thin film, will the deformation of the thin film cause a change in the capacitance value between the electrodes? Similarly, by reasonably arranging multiple capacitance units and analyzing the differences in capacitance values of each unit, can the position information of the pressure be inferred?
II. Applications in the Medical Field
(1) Monitoring in Rehabilitation Treatment
During the process of rehabilitation treatment, position-sensitive thin-film pressure sensors can be placed on the soles of patients’ feet, palms and other parts. For example, for a patient who is recovering from a leg injury and undergoing rehabilitation training, when the sensor is placed on the sole of the foot, it can accurately sense the distribution and changes of pressure in different areas of the sole when the patient is walking, standing and performing other actions. Can doctors adjust the rehabilitation training plan in a timely manner according to these data to ensure the maximization of the rehabilitation effect by understanding whether the patient is exerting force evenly and whether they are overly relying on a certain area?
(2) Evaluation of Prosthesis Fitting
For patients wearing prostheses, position-sensitive thin-film pressure sensors are installed at the contact area between the prosthesis and the residual limb. They can monitor the magnitude and position information of the pressure between the residual limb and the prosthesis in real time. If the pressure at a certain position is too large, it may cause discomfort to the residual limb and even problems such as abrasion and pain. Can the prosthetist fine-tune the prosthesis, such as adjusting the shape of the inner lining and the distribution of the cushioning material, according to the data fed back by the sensor to improve the fitting of the prosthesis and the comfort of the patient?
III. Applications in the Sports Field
(1) Analysis of Athletes’ Movements
In sports training and competitions, position-sensitive thin-film pressure sensors are of great use. Taking track and field athletes as an example, by laying the sensors on the soles of running shoes, the pressure situation in various parts of the soles of athletes during the running process can be accurately measured. Can coaches provide targeted guidance on the running techniques of athletes according as these data to help them improve their performance by understanding their landing methods and force application points?
(2) Optimization of Sports Equipment
In some ball games such as basketball and football, position-sensitive thin-film pressure sensors can be embedded in the balls or in the gloves, protective gear and other equipment of athletes. By monitoring the position and magnitude of the pressure when athletes are touching or hitting the balls, can the performance of the equipment be evaluated? For example, can the shock absorption effect of basketball shoes be judged as good or not, and can the grip strength of gloves be judged as appropriate or not? According to the data fed back by the sensor, can sports equipment manufacturers optimize and upgrade their products to meet the higher demands of athletes?
IV. Applications in the Smart Home Field
(1) Monitoring Sleep with Smart Mattresses
By placing position-sensitive thin-film pressure sensors inside the mattress, they can sense the sleeping posture of the sleeper on the mattress and the distribution of pressure on various parts of the body in real time. Can the sleep quality of the sleeper be understood by analyzing these data, such as whether they are turning over frequently and whether there is poor blood circulation caused by excessive local pressure? Moreover, can the smart mattress automatically adjust parameters such as the softness and hardness of the mattress according to these data to provide a more comfortable sleeping environment for the sleeper?
(2) Improving the Comfort of Smart Seats
When position-sensitive thin-film pressure sensors are applied in smart seats, they can monitor the distribution of pressure on the buttocks and back and other parts of the users when they are sitting on the seats. When it is detected that the pressure at a certain part is too high, can the seat automatically adjust the shape, inflation degree and other aspects of the seat cushion or back cushion to relieve the discomfort of the users and improve the comfort of the seats? This is especially suitable for office workers who sit on seats for a long time or long-distance travelers.
V. Development Prospects and Challenges
The development prospects of position-sensitive thin-film pressure sensors are very broad. With the continuous progress of science and technology, their performance indicators such as sensitivity, accuracy and reliability will continue to improve. Are they expected to play an important role in more emerging fields such as virtual reality and augmented reality experience devices? For example, can more realistic interaction experiences be achieved by sensing the action pressure and position of users in virtual environments?
However, there are also some challenges at present. On the one hand, the cost of sensors is relatively high, which restricts their large-scale popularization and application to a certain extent. On the other hand, under complex environments such as high humidity and high temperature conditions, will the performance stability of the sensors be affected? Further research and development are needed to adapt to a wider range of use environments.
Position-sensitive thin-film pressure sensors, with their unique functions, have already shown great application value in non-industrial fields such as medicine, sports and smart homes. It is believed that with the continuous improvement and breakthrough of technology, they will bring more convenience and surprises to our lives.